- if expecting more than 100s items/day in your workflow, perhaps its better to look into dataserver/client/direct SQL instead of trying to reverse engineer plugin docs and learn horror XUL on the way (also make sure its a plugin, not an improvement to existing translator).
Otherwise: UI operations should work on item groups by default.
- to avoid dealing with XUL overlays [1] (though I see cashweaver/zotero-add-pdf-from-generator already has that) and keypresses like in [2] or [3]: hack zutilo [4] to run your function by binding a shortcut to "document.getElementById('zotero-view-tabbox') ..."
- try ArchiveBox as well? [5] with built-in queue/instance management, its a bit better than selenium grid or headless chrome + print to pdf
If you're OK with using modified client as a "get things done quick" type of hack (imo not worth money or effort to do it as plugin from scratch; started it with a backlog of some hundreds k entities, so maybe a bit biased) instead of plugin approach, drop me a message maybe.